The present invention relates to an apparatus and a method for inserting a filter into a groove formed in a substrate such as a groove crossing a waveguide of a planar lightwave circuit (PLC).
A conventional method for inserting a filter into a groove can be found in the paper titled xe2x80x9cAutomatic Machine for Loading Filter Film to Planar Lightwave Circuitxe2x80x9d, presented in 1998 by Ishigami et al., on Electronics 1, page 330 in general conference papers of the Institute of Electronics, Information and Communication Engineers (IEICE) of Japan. In this method, the position of a groove is determined on the basis of the image data obtained by reading markers provided on the PLC by a camera, a laser measuring machine is used to determine the position of the filter to be inserted into the groove, the filter is moved to an optimum position according to the position information, and the filter is inserted into the groove.
The conventional method described above, however, requires a camera for reading markers and a laser measuring machine for measuring the film position, and the whole apparatus used to insert a filter would become expensive, resulting in a rise in the cost of the PLC module to be fabricated. In addition, because it takes much time to read the markers and to measure the filter position, it would take much time to insert the filter into the groove.
It is an object of the present invention to provide an apparatus and a method for inserting a filter into a groove formed in a substrate that make it possible to insert the filter into the groove quickly through simple operations.
According to the present invention an apparatus for inserting a filter into a groove formed in a substrate, comprises a head portion which holds a strip of filter; and a support portion which supports the head portion. The head portion includes a guide portion which has an outlet through which the filter is fed, and which guides the filter toward the outlet; a pair of plate members which are disposed on both sides of the guide portion to surround the guide portion, with a space left between tips of the plate members and with vicinities of the tips provided at a given angle; and a pair of blades which are disposed on the tips of the plate members, edges of the blades facing each other with a space wider than thickness of the filter. The apparatus is configured in such a manner that when the head portion is pressed against a V-shaped channel comprising a pair of inclined surfaces by the support portion, with the vicinities of the tips of the plate members in face-contact with the inclined surfaces of the V-shaped channel, elastic deformation occurs in the pair of plate members, narrowing the space between the edges of the pair of blades, and when the head portion is moved off the V-shaped channel, the space between the edges of the pair of blades expands to an original width.
The support portion may comprise a pair of arms which are disposed on both sides of the head portion; a supporting bar which is attached to the arms and supports the head portion so that the head portion can be moved in a direction orthogonal to a feeding direction of the filter; and a pair of springs which are disposed on the pair of arms, each spring applying a force to press each face of the head portion facing the arm.
The apparatus may further comprise a thrust bar which supports the support portion in such a manner that the support portion can be rotated about an axis passing a center of the head portion and extending in the feeding direction of the filter; and a thrusting spring which transfers to the support portion a force applied to the thrust bar in the feeding direction of the filter.
The head portion may comprise a pair of rollers which move the filter toward the outlet; and a driving mechanism for driving the pair of rollers.
The head portion may comprise a path of incoming light which extends at an angle with respect to a surface of the filter and reaches the guide portion; a light emitting element which emits light to the filter through the path of incoming light; a path of reflected light which extends at an angle with respect to the surface of the filter and reaches the guide portion; and a light receiving element for receiving the light which is emitted from the light emitting element and reflected from the filter and passes through the path of reflected light.
According to another aspect of the present invention, a method for inserting a filter into a groove formed in a substrate uses a filter insertion apparatus, which comprises a head portion which holds a strip of filter and a support portion which supports the head portion, the head portion including a guide portion which has an outlet through which the filter is fed and which guides the filter toward the outlet, a pair of plate members which are disposed on both sides of the guide portion to surround the guide portion, with a space left between tips of the plate members and with vicinities of the tips provided at a given angle, and a pair of blades which are disposed on the tips of the plate members, edges of the blades facing each other with a space wider than thickness of the filter. The method comprises the steps of putting a guide member onto a substrate of optical circuit having an optical waveguide; forming a V-shaped channel in the guide member; forming a filter insertion groove directly below the V-shaped channel in the substrate of optical circuit; putting out the filter by a given length from the outlet of the guide portion of the apparatus; inserting the filter put out of the outlet of the guide portion into the filter insertion groove by pressing the apparatus toward the V-shaped channel of the guide member, with vicinities of the tips of the plate members of the apparatus in face-contact with inclined surfaces of the V-shaped channel in the guide member, narrowing space between edges of the pair of blades to cut the filter coming out of the outlet of the guide portion by pressing the apparatus further toward the V-shaped channel in the guide member; and moving the head portion off the V-shaped channel in the guide member.